Heterostructure/Pore-Size Ordered SnO2 Porous Films and Multiphysical Mechanism for Rapid Detection of Ethanol

In the work, hetero-structure and hetero-pore-size based on SnO² are fabricated by the two-dimensional colloidal crystal template method, and the effects of morphological richness and pore size of ordered porous films on gas-sensitive properties were systematically investigated. The sensor based on ordered porous films possesses excellent fast response, stability and detection limit down to 1 ppm to ethanol. To explain the sensing mechanism, a novel multi-physics field coupled analysis method, such as electrical and hydrodynamic, was used to quantify the gas adsorption on the gas-sensitive film surface and the internal current density distribution. The results demonstrate that the simulation can explain the experimental phenomena well.